A tape cassette transport records data on and retrieves data from magnetic tape housed in a cassette used in conjunction with the transport. Streaming type transports have more rigorous requirements than an ordinary cassette transport in that they must record and retrieve the data at continuous high rates of speed with short abrupt start and stop operations. Generally, they are intended to provide a reliable low-cost storage backup for present-day rigid disk drives such as the 51/4 inch Winchester drive. One example of such a transport now in use is shown in U.S. patent application Ser. No. 374,046, filed May 3, 1982, now U.S. Pat. No 4,514,775, entitled Streaming Tape Cassette Transport, owned by the assignee of the present application.
From a marketing standpoint, the streaming tape transport must have the same form factor or exterior dimensions as the disk drive to enable it to fit in the same receptacle in the terminal or housing that holds the disk drive. For example, the standard Winchester drive is 31/4 inches high, 53/4 inches wide and about 8 inches long or deep. Consequently, if it is to function as a back-up or replacement for that drive in a standard terminal or housing, the streaming transport must have the same outside dimensions and, indeed, the transport disclosed in the above-mentioned application does.
In general, however, cassette tapes are unable to store much more information than can be stored on a disk. Consequently, it would be desirable to increase the amount of data that can be stored on cassette tape in the volume presently occupied by a standard streaming cassette transport or disk drive.
One way of accomplishing this, of course, is to design the cassette transport so that it is one-half as high as a conventional transport of this type (i.e. 1.625 inches vs. 3.25 inches) so that two such transports with associated tape cassettes can be located in the same envelope or receptacle formerly occupied by one such transport or comparable disk drive, thereby doubling the storage capacity. Yet, if this is to be done, the "thin" transport must still be reliable and easy to use and operate at the same continuous high rates of speed between abrupt start and stop operations as do present-day streaming transports.